This project will address the therapy of mesothelin expressing tumors by developing and testing engineered[unreadable] T cells with potent antitumor cytotoxicity. Mesothelin is a tumor-associated antigen that is frequently over[unreadable] expressed on mesothelioma, non-small cell lung cancer, pancreatic and ovarian cancers. The strategy to be[unreadable] used is the "T-body" approach, which employs genetically reprogrammed, patient-derived lymphocytes[unreadable] transfected with a novel chimeric receptor that contains combinations of the signal transduction domains of[unreadable] 4-1BB (CD137), CD28, and CD3zeta as well as anti-mesothelin scFv (anti-meso-CD28-41BB-zeta). The central[unreadable] hypothesis to be tested is that previous trials of adoptive therapy for cancer have used insufficient numbers[unreadable] of cytotoxic T lymphocytes (CTL) that have shown inadequate engraftment, persistence and effector[unreadable] function to self antigens. Presently, we are the only laboratory in the world that is actively testing lentiviral[unreadable] modified T cells in the clinic, and in that trial we have demonstrated safety and prolonged lentiviral gene[unreadable] transfer. The following three specific aims will test the hypothesis that engineered human T cells expressing[unreadable] an anti-mesothelin-CD28-41BB-zeta chimeric receptor will have potent antitumor activity in vitro and in vivo by:[unreadable] (1) developing and optimizing the anti-meso scFv vector. The avidity and the cytosolic signaling modules will[unreadable] be optimized to obtain highly efficient lentiviral vectors that retarget T cells to specifically kill tumor cells that[unreadable] express mesothelin at low effector to target ratios in vitro; (2) carrying out in vitro experiments to optimize[unreadable] the effector functions of anti-mesothelin scFv CD28-41BB-zeta T bodies. Experiments will determine optimal[unreadable] conditions for redirected T cell serial killing, cytokine production and proliferation, and compare this to[unreadable] natural MHC restricted CTLs; and (3) performing in vivo experiments in immunodeficient NOD/SCID/beta2null[unreadable] mice xenografted with human tumors that express mesothelin. These experiments will test the hypothesis[unreadable] that vectors with high affinity scFv receptors and 4-1BB and CD28 signaling modules will have the most[unreadable] potent anti-tumor effects. Finally, the engraftment, persistence and antitumor effects of chimeric T cells[unreadable] given by intravenous and intraperitoneal routes will be compared using bioluminescence imaging. In[unreadable] summary, an outstanding team of basic and translational scientists has been assembled that will develop[unreadable] and test a universal T cell receptor to target some of the most common and drug resistant tumors.[unreadable] Lay Description. A common reason for failure of immunotherapy of epithelial tumors is that the[unreadable] immune system does not generate sufficient numbers of T cells to eradicate the tumor cells. It is now[unreadable] possible to use lentiviral vector technology to engineer T cells with potent and specific antitumor effects.[unreadable] This project will evaluate engineered T cells that target mesothelin that is overexpressed on both uncommon[unreadable] tumors such as mesothelioma and a variety of commonly lethal tumors including pancreatic, ovarian and[unreadable] non-small cell lung carcinoma.[unreadable]